Private schools would leave an £800 million "hole" in teachers' pension pot if a planned hike in contributions forces them to pull out of the scheme, according to figures seen by Tes.

Schools were left reeling last month after being told their payments to the Teachers' Pension Scheme (TPS) will rise by more than 40 per cent from September next year.

Internal calculations by the Independent Schools Council (ISC), revealed in emails seen by Tes, estimate private schools currently contribute £590 million a year to the TPS, around 10 per cent of the total.

Teachers, who on average put 9 per cent of their salary into their pension pot, contribute a further £225 million themselves.

Combined, the ISC estimates the TPS would be left with a “total hole in the order of around £815 million” if independent schools withdrew from the scheme.

The figures add to warnings that the potential hike in employer contributions to 23.6 per cent, up from 16.48 per cent now, could be the final straw for schools already struggling to make ends meet.

ISC chair Barnaby Lenon said the council's members were considering leaving the scheme as part of a range of options to address the impact of the pension hike.

"There are many schools thinking about it but it will be impossible to say how many will eventually withdraw from the TPS," he said.

"Nobody wants to withdraw from the TPS, but some schools may be forced to do so for financial reasons."